This website uses cookies to deliver some of our products and services as well as for analytics and to provide you a more personalized experience. Click here to learn more. By continuing to use this site, you agree to our use of cookies. We've also updated our Privacy Notice. Click here to see what's new.

This website uses cookies to deliver some of our products and services as well as for analytics and to provide you a more personalized experience. Click here to learn more. By continuing to use this site, you agree to our use of cookies. We've also updated our Privacy Notice. Click here to see what's new.

About Optics & Photonics TopicsOSA Publishing developed the Optics and Photonics Topics to help organize its diverse content more accurately by topic area. This topic browser contains over 2400 terms and is organized in a three-level hierarchy. Read more.

Topics can be refined further in the search results. The Topic facet will reveal the high-level topics associated with the articles returned in the search results.

Abstract

A two-dimensional (2D) spectral SPR sensor based on a polarization control scheme is reported in this paper. The polarization control configuration converts the phase difference between p- and s- polarization occurring at surface plasmon resonance (SPR) into corresponding color responses in spectral SPR images. A sensor resolution of 2.7 x 10−6 RIU has been demonstrated, which corresponds to more than one order of magnitude resolution improvement (26 times) comparing to existing 2D spectral SPR sensors. Multiplex array detection has also been demonstrated with the spectral SPR imaging sensor. In a 8 x 4 sensor array, 32 samples with different refractive index values were monitored simultaneously. Detection on bovine serum albumin (BSA) antigen-antibody binding further demonstrated the multiplex detection capability of the 2D spectral SPR sensor for bio-molecular interactions. The detection limit is found to be 21ng/ml, which is 36 times better than the detection limit previously reported by phase imaging SPR sensors. In light of the advantages of high sensitivity, 2D multiplex detection and real-time response, the spectral SPR imaging sensor can find promising applications in rapid, high throughput, non-labeling and multiplex detection of protein array for proteomics studies, biomarker screening, disease prognosis, and drug discovery.

Figures (6)

Fig. 1 (a) Experimental scheme of the Spectral SPR imaging sensor based on the polarization control scheme (b) The orientation angle shift α′of the ellipse of the light, which is produced by the phase difference Δφ between the p- and s- polarization occurring at surface plasmon excitation.

Fig. 4 The response curve of the spectral SPR imaging sensor in the refractive index range between 1.3333 - 1.3454 RIU. It shows the sensor responds for different concentration salt solutions ranged from 0%-7%. It shows that the sensor response increases with increasing refractive index values (RIU) and a linear response (from 23.1 to 61.2 Hue unit) is shown in the refractive index range between 1.3333 – 1.3365 RIU. The error bar is obtained from the standard deviation (S.D.) between 5 averaged measurement data.

Fig. 6 (a) Bovine serum albumin (BSA) antigen (1mg/ml) was immobilized in four different locations of the protein array (red spots). The non-specific protein sample (glucose oxidase, 1mg/ml) served as the negative control of the experiment (white spots). (b) Spectral SPR image of the protein array, when the protein was kept in buffer solution. (c) Spectral SPR image of the protein array, which is taken 41 minutes after the injection of BSA antibody (0.01mg/ml). The specific binding between BSA antigen-antibody changed the spectral responses in the BSA antigen sites from red to green color, while no significant color variation were observed in the non-specific sensor sites (glucose oxidase).